$dir: left;
$space: 10px;
$bg:red;
.nav{
     margin-#{$dir}:  $space;
     padding-#{$dir}: $space;
     border-#{$dir}: $space;
}

$width:100px;
$height:200px;
$smallp:59px 36px $width/2 $height/3;

.plane{
    width:nth($smallp,1);
    height:nth($smallp,1);
    left:nth($smallp,1);
    top:nth($smallp,1);
    }


ul{
    li{
        list-style: none;
        float:left;
        a{
            display: block;
            height:$height/2;
            width:$width;
            background:$bg;
            &:hover{
                background: yellow;
            }
            
        }
    }
}

@mixin border-radius($size){
    -moz-border-radius: $size;
    -webkit-border-radius: $size;
    border-radius:$size;
}



#box{
     float:left;
    height:$height;
    width:$width;
    @include border-radius(10px);
    background: $bg;
}


